Exteriors Leads Meeting Notes

09/24/2024

Must haves for MS16:

• Length of 5.5-5.8

• Is maximizing length optimal?

  • Reduces pressure drag, increases friction drag

• Adjust split line between aerobody tub and roof

  • No negative draft

  • Split line at vertical part of the aerobody

• Canopy

  • Cut line changed

    • Needs to “flatten out”

Exteriors goals for MS16:

• Nose

  • Do not bring it up, keep it lower

    • Easier to manufacture

    • Not as much camber on the roof

    • Space for battery/other systems in the nose now?

• Bring Point where roof “hangs over” tub more towards the front

• Split line needs to be at a point where the roof and tub profiles are vertical

• Ensure tail is not “flimsy”

• Canopy

  • Increase canopy length

    • length/height ratio as close to 6 as possible

• Tail

  • Don’t come to a point, come to a box instead to fit license plate

  • Back panel in the layup with the tub

Research to be done:

• Teardrop vs straight side-edge bottom profile?

• Optimal CD/frontal area ratio

• Friction drag vs. pressure drag (what has the bigger effect in our situation)

10/01/2024

• Canopy

  • Task Idea: Parametric Canopy Model

    • Can eventually be extended to be a parametric model for the whole aerobody

    • Can be given to any members who have done onboarding

• Friction vs Separation Drag (how much can we extend the car by?):

  • In general, pressure drag should be the dominant drag component over friction drag [Goro Tamai: The Leading Edge].

  • On a solar car where pressure drag should be less noticeable, friction drag is more prevalent.

  • We should aim to eliminate our pressure drag before friction drag

    • Friction drag can be mostly overcome by achieving a smoother surface finish on the car.

• Dynamic wheel cover task doc complete

  • Review in meeting

• Teardrop vs straight side-edge bottom profile?

  • Need bottom and top profiles for the car first

  • make the dimensions for these parametric

  • Can start design with just these two shapes while waiting for other subteams

• Aerodynamics 101 NEXT Tuesday

• Potentially post SLDPRT file for design sprint #1

• Teardrop vs straight side-edge bottom profile?

  • Considerable difference in Cd, needs to be compared against the difference in frontal area

  • need to find optimal ratio Cd and frontal

• Wheel covers

  • up and down hinges (opening on the underside of the car)

• Design plan

• initial bottom profile wheel distance based on dynamic wheel cover calc is 333.2mm+track width. for now we assume tack distance is 850mm.

-new research task mock up(canopy length/solar)

-wheel cover design

-need to find optimal ratio Cd and frontal

-solar array layout task

10/25/2024

• Composites order put in

• New tasks created for members who have completed mouse

  • Need people to start research tasks

• Rib Panel R&D

  • Want do do infusion over wet layup

  • Panels Need to be as light as possible

• Task documentation

  • Google Drive folder of documents

• Canopy length research

  • Finding ideal length for canopy while also accommodating solar

• Waterproofing task

• Looking into shortening length of car +widening roof for solar array + narrowing bottom profile because our steering angle would be less

• CFD 101/Layup demo on Tuesday November 5th

11/12/2024

• Steering Angle?

  • Still waiting on calcs

  • No need to spec springs for dynamic wheel covers

• 2D sims for side profile

• Research on performance of different airfoils

  • Low drag = good

• Canopy design task

  • Sim different iterations in SimScale

• Composites Workshops

  • Monday Nov. 18, Thursday Nov. 2

  • 1 infusion per group

    • 3 maybe 4 groups

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11/19/2024

• New tasks

  • Wheel cover latching

    • Due end of next term

  • Canopy design

    • Introduce next week

• Array layout task modification

  • Due next Tuesday

• Steering angle?

• 2D sims

  • Ansys or XFLR5

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11/26/2024

• Ansys for 2D sims

  • Will have conclusions when we come back from winter break

• Wheel cover latching task

  • Initial designs received, 3D printing phase

  • Will try make tab geometry flush with aerobody wall

• Canopy design task

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• Array layout

  • Task done, roof width will be around ~1.6m

• Need value of how much the steering angle that the wheel covers will open at increases by in order to determine whether we want a longer (>2.64m) or shorter (<2.64m) wheelbase

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